Periodically, fuel injectors must be removed from an engine for cleaning, repair, or replacement. This often times is very difficult because of the crowded nature of the cylinder head or the intake manifold in which the injectors are located. This is especially true of diesel engines wherein the injectors feed fuel directly into the combustion chamber. A particular example is the Cummins "855" series diesel engines where the fuel injectors are located in the cylinder head between the intake and exhaust valves. Very little space exists for positioning a tool in these close quarters.
One particular tool is disclosed in Webb, U.S. Pat. 4,293,992. Webb has a threaded bolt which fits into a matching threaded hole already located in the cylinder head. An arm fits under a flange in the fuel injector and as the bolt is turned, the flange is pulled upward, thus, removing the injector from its bore. Not all engines are equipped with this auxiliary threaded hole.
Another fuel injector puller was proposed by Bernat, U.S. Pat. 4,780,942, which used an intermediate member between the grasping portion and the handle portion to provide a fulcrum to provide the necessary force to remove the injector from its bore. This tool is designed to remove fuel injectors from the intake manifold of engines and although adequate for its intended purpose, this particular design does not adapt itself well to removing injectors from diesel engines where the injectors are nested between the valves of the engine.
A need, therefore, exists for a simple, small tool which can be inserted down between the valves of an engine to gently remove a fuel injection unit from its bore without damaging the fuel injector.